For the transmission and storage of audio signals in digital form, different coding methods for achieving bit rate reduction have become known so far (DE 3639753 C2) which are used for the coding of a monophonic or stereophonic audio channel. If the bit rate of two audio channels that belong together is to be reduced, each individual channel by itself can be subjected to a bit rate-reducing coding and can subsequently be transmitted or stored. The bit rate reduction, however, can be made more effective by not only utilizing the masking characteristics of the human ear in each individual audio channel taken by itself for the bit rate reduction but, in addition, by also utilizing the inertia of the hearing sensation in stereophonic hearing as well as the stereophonic masking characteristics of the human ear (NL 9000338).
For some applications (such as, for example, for future HDTV applications), however, it is intended to transmit, record or reproduce more audio channels of a multi-channel signal than the usual two (stereophonic) used so far. Naturally, in such a case all audio channels can be individually subjected to a bit rate-reducing coding before they are transmitted or stored. Nevertheless, the bit rate necessary for the transmission of multi-channel audio signals increases along with the number of channels that are to be transmitted. Because of the very high costs for the additionally required channel capacity compared to stereophonic transmission, this circumstance does not result in an easy implementation of such a multi-channel transmission method.